There are two main types of closed chest drainage bottles used in clinical practice, one is the common water-sealed bottle type drainage bottle and the other is the three-chamber closed chest drainage bottle. The main purpose of chest drainage is to drain gas or fluid from the chest cavity. When the purpose is to drain gas alone, there is usually no need to replace the closed chest drainage bottle. When the purpose is to drain fluid from the chest cavity, the normal water seal bottle type drainage bottle does not need to be replaced unless it is severely contaminated, only the water seal fluid needs to be replaced periodically. If a three-chamber closed chest drainage bottle is used, it needs to be replaced only when the fluid in the drainage bottle is full, usually once every 3-5 days.